Acoustic wave devices are employed in filters for mobile communications. The acoustic wave device includes acoustic wave resonators formed on a substrate. Wiring lines formed between the acoustic wave resonators are sometimes formed adjacent to each other as disclosed in Japanese Patent Application Publication No. 2000-114916. There has been known forming a wiring line connecting acoustic wave elements formed on a substrate or a wiring line connecting an acoustic wave element to an external terminal by liftoff as disclosed in Japanese Patent Application Publication Nos. 2003-101373 and 2003-174056.